EMP Bomb

From TaRapedia

EMP Bombs do a massive amounts of EMP damage (typically in the thousands), and can crit. To use it, you simply place it in the area you would like to detonate it, and it will explode in a few seconds. It will not damage you or your group. However, you can only have one bomb placed at a time. If you place another EMP Bomb, your first one will simply vanish.

EMP Bombs are best used against mechanical or electrical targets that have high HP and regeneration. Cannons, force fields, and mechanical mini-bosses like Rotting Sal are excellent targets for EMP Bombs.